Electrostatic separator.



H. GoMsTooK.

BLEGTROSTATIG SEPARATOB.

APPLIUATION FILED JUNE 9, 1911.

HARRY COMSTOCK, OF MENEVELLE, 'NEW' YORK.

ELECTROSTATC SEPARATOR.

Specification of Letters atent.

Patented Sept. t5, 119141.

Application filed June 9, 1911. Serial No. 632,134.

To all whom it may concern Be it known that ll, HARRY Corrsroon, acitizen of the United States, residing at Mineville, county of *sseX,and State of N ew York, have inv ted'certain new and useful Improvementsin Electrostatic Separatore, of which the following is a specification.

rlhe invention relates to such improvements and consists of the novelconstruction and combination of parts hereinafter described andsubsequently claimed; also the hereindescribed method.

Reference may be had to the accompanying drawings, and the referencecharacters marked thereon, which form a part of this specification.

Similar characters refer to similar parts in the several figurestherein.

Figure 1 of the drawings is a view in side elevation of my improvedelectrostatic separating mechanism. Fig. 2 is a diagrammatic viewillustrating my invention Wired for the employment of a three-phase ourrent. Fig. 3 is a top planview of part of y the frame, showing the'manner of mounting the electrostatic plate.

lt is well known that mixed particles o materials of different electricconductivity can be separated from one another by the use ofelectrostatic apparatus; and various devices for this purpose have beendevised wherein a statically charged body has been employed forrepelling particles attracted to its surface and charged thereby.

The principal object of the present invention is to render moreeffective and certain the separation electrostatically of particles ofdi'erent degrees of conductivity. This 1 am able to accomplish bycombining with an electrostatically charged plate, and means forconveying the mixture of particles to be separated into theelectrostatic field of said plate, a traveling body interposed betweensaid electrostatically charged plate and said mixture of particles,adapted to intercept and mechanically remove from the.

electrostatic field those articles which are most strongly attracted ysaid plate.

Other objects of the invention will appear in connection with thefollowing description. v

Referring to the drawings l`wherein the invention is shown in preferredform, `l,

represents the frame of the apparatus, upon which is rotatively mounteda pair of rolls or drums, 2, carrying a belt, 3, of non-conductivematerial. Power is applied to one of said rolls through the belt, 4, andpulley 5. A platform, 6, is mounted upon said frame by means ofadjusting screws, 7, whereby the height of said platform can be alteredfrom time to time as desired. Rotatively mounted upon said platform area pair of rolls or drums, 8 and 9, carrying a belt, 10, of conductivematerial such as metal. Power is applied to one -of said rolls, 8, bymeans of a belt, 11, and pulley 12. The roll or drum, 9, is ofconductive material, as metal. Carried by the roll, 9,

v are a series of tappets, 13, adapted to operate in one direction anagitator, 14C, one end of which is adapted to jarringly engage the upperstretch of belt, 10, when released to the action of its controllingspring, 15, each time a tappet, 13, passes from beneath said agitator.

The belts and rolls are so arranged that the lower stretch of the belt3, overlaps and extends in close proximity to the upper stretch of thebelt 10.

An electrostatic plate, 16, is supported just above the lower stretch ofbelt, 3, approximately in vertical line with the outer edge of the rollor drum 9.

The plate, 16, is mounted upon the top bar of the frame by means of ascrew-bolt, 30, which passes through a slot, 31, extendinglongitudinally of the frame, whereby the position of the plate, 16, canbe adjusted longitudinally of the machine with reference to the roll ordrum, 9; and, by using a washer, 32, of greater or less thickness, thedistance of the plate, 16, from the lower stretch of belt, 3, can bevaried as desired.

A dielectric or division-plate, 17 extends more or less into the anglewhere the belts, 3 and 10, diverge adjacent to the roll or drum 9.

The dielectric divider, 17, is pivotally mounted at, 20, in a slot, 21,in the frame of the machine, whereby the upper end of said dielectricdivider can be located at any desired point in said angle. l

A feed-hopper, 18, is adaptedto deliver the mixed material to beseparated upon the upper stretch of belt, 1.0,at a point remote from theroll or drum, 9, toward which said upper stretchof belt travels. rlheneighboring stretches of the belts, 3 and 10, travel in the samedirection, but the speed of the belt, 3, is much greater than that ofbelt 10.

A gas-burner, 34, is located beneath the chute, 22, leading from thehopper, 18, and serves as a means for heating the material to beseparated as the same passes down the chute.

rllhe electrostatic plate, 16, is connected by wire, 23, with a lmownform of generator of electric potential, and the roll, 9, is connectedby wire, 24, with the ground, or the same may be a return wir connectedwith said generator. rlhc belt, 10, androll or drum, 9, being ofconductive material, are in electrical connection with each other.

The operation of the apparatus is as iiollows: The material to beseparated is deposited in the hopper, 18, and passes gradually down thechute, 22, being thereby deposited in a thin sheet or layer upon theupper stretch of belt, 10which carries the material so deposited alongbeneath the lower stretch of belt, 3, to a point opposite theelectrostatic plate i6. '.lhe more conductive particles in said mixtureare strongly attracted by the electrostatic plate, 16, and drawn towardthe same until they are brought into Contact with the lower stretch 01"'the'belt, 3, which by 'trictional engagement with said attractedparticles quickly carries them out of the static ield to a point beyondthe dielectric divisionplate, 17, upon which said particles tall fromthe belt,3, as they are relieved from the attractive influence of theplate 16.

The less conductive particles either remainl in contact with the belt,10, until they tall by gravity as said belt passes around the roll, 9,or if said particles leave the upper stretch of the belt, 10, they donot do so with suiicient force to pass over the upperl edge of thedivision-plate 17.

Agitating the belt, 10, by means o2 the agitatoryld, tends to uncoverthe more con ductive particles, so as to permit them to be freelyattracted by the plate, 16, without intle'rference by overlying lessattracted partic es.

lt is well known in the art that certain' materials, such as quartz,tourmaline, &c., are more easily electrified while under such conditionsthat their temperature is chang: ing. In treating such materials as havethis characteristic, l' prefer to impart to the material to beseparated, before introducing the same into the electrostatic field, anahnormal temperature, that is a temperature materially higher ormaterially lower than that of the space between the electrostatic poles,so that as the material is passing through the electrostatic ield itstemperature will be changing and tending to again become normal.

1,1 idees The burner, 34, or other known heating means may beconveniently employed to impart to the material such an abnormaltemperature. When it is not desired to heat the material, the burner,34, may be omitted. By means of the screws, 7, the upper stretch of thebelt, 10, can be moved nearer to or further from the lower stretch ofthe belt, 3, to meet different conditions in use. The

relative speeds of the belts, 3 and 10, can

'also be varied ,in use.

For certain purposes of the invention any source of electric potentialcan be employed. for electrifying the plate, 16, and the current may beeither direct or alternating. l prefer, however', to use an alternatingcurrent; and, for certain purposes oit the invention, l prefer to employa polyphase alternating current, and in Fig. 2 ll have illustrated theuse of a three-wire threephase circuit with two electrostatic plates,

25 and 26, connected, respectively, with two of the wires, 2'? and 2S, athird wire, 29, being connected with the roll 9. i

The difference in potential and the tre.- quently changing potentialrelationship be@ tween the plates, 25 and 26, serve toiturther agitatethe material attracted by said plates, as such material is carried pastsaid plates successively, thus yfacilitating the separation of the moreconductive particles from less conductive particles which mightotherwise adhere thereto.

What l claim as new and desire to secure by Letters Patent is'- l. in astatic'separating apparatus, and in combination, an electrostaticallycharged plate; means for carrying material tc be separated into thefield of said plate; and traveling means interposed between saidmaterial and said electrostatically charged plate for preventing contactof the material with said plate, and for carrying out of the staticfield material attracted by said plate.

2. ln a static separating apparatus, and in combination, a belt ofnon-conductive material; an electrostatically charged plate supportedabove the lower stretch of said belt; means for moving said belt; andmeansetor carrying material to be separated beneath said belt into theield of said plate. i

3. ln a static separating apparatus, and in combination, a belt ofnon-conductive material an electrostatically charged plate supporte-dabove the lower stretch of said belt; means for movingsaid belt; and anelectrostatically charged belt beneath said noirconductive belt forcarrying material to be separated into the field of said plate.

4. ln a static separating apparatus, and in. combination, a belt ofnon-conductive maics terial; an electrostatically charged plate sup- 1,1rasees plate; and a conveying-belt ot conductive material passing aroundsaid roll in electrical connection therewith.

5. ln a static separating apparatus, and

in combination, a belt of non-conductive material; an electrostaticallycharged plate supported above the lower stretch of said belt; means formoving said belt; an electrostatically charged belt beneath saidnon-conductive belt for carrying material to be separate'd into thetield of said plate; and means whereby one of said belts can be adjustedtoward and from the other. a

6. ln a static separating apparatus, and in combination, a belt ofnon-conductive material; an eletrost'atically charged plate supportedabove the lower stretch of said belt; means for moving said belt; anelectrostatically charged belt beneath said non-conductive belt forcarrying material to be separated into the field of said plate; meanswhereby said plate can be adjusted toward and from said lower stretch ofnon-conductive" belt; and means whereby one ont' said belts can beadjusted toward and from the other.

7. In a static separating apparatus, and in combination, a belt ofnon-conductive material; an electrostatically charged plate supportedabove the lower stretch of said belt; means for moving said belt; anelectrostatically charged belt beneath said non-conductive belt forcarrying material to be separated into-the field of said plate; andadielectric separating plate extending into the angle of separation ofsaid belts.l

8. In a static separating apparatus, and in combination, a belt ofnon-conductive material; an electrostatically charged plate supcportedabove the lower stretch of said belt; means for moving said belt; anelectrostatically charged belt beneath said non-conductive belt forcarrying material to be separated into the ield of said plate; adielectric separating plate extending into the angle of separationof'said belts; and means whereby said separating plate can be adjustedmore or less into the electrostatic field.

9. ln a static separating apparatus, and in combination, a belt ofnon-conductive material; an electrostaticallycharged plate supportedabove the lower stretch of said belt; means for moving said belt; anelectrostatically charged belt beneath said non-conductive belt forcarrying material to be separated into the iield of said plate; meanswhereby said plate can be adjusted toward and from said lower stretch ofnon-conductive belt; means whereby one of said belts can be adjustedtoward and from the other; a dielectric separating plate extending intothe angle of separation of said belts; and means whereby said separatingplate can be adjusted relatively to said belts.

10. ln a static separating apparatus, and in combination, a lower beltof conductive material; an upper belt of nonconductive material, saidbelts being arranged with the upper stretch of the lower beltapproximately parallel and in proximity to the lower stretch of theupper belt; two electrostatic plates supported above the lower stretchof said upper belt; and means for connecting said electrostatic platesand said lower belt with the respective elements of a three-wirethree-phase electric circuit.

In testimony whereof, ll have hereunto set my hand this 31st day of May,1911.

HARRY COMSTUCK. Witnesses. j

H. F. Prec, T. SWIFT.

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